Antonyms of "pro tempore" would be phrases or words that convey permanency or long-term status. Antonyms could include phrases such as "permanent," "fixed," "lasting," or "stable." Alternatively, one could use words such as "full-time," "lifelong," or "regular" to describe the opposite of the temporary nature of pro tempore. Another possible approach to finding antonyms for pro tempore is to use contrasting phrases that indicate opposite extremes of time, such as "eternal" or "brief," or "everlasting" and "momentary." In general, the opposite of pro tempore is any concept that connotes permanency, perpetuity, or stable status.